A typical image sensor senses light by converting impinging photons into electrons that are integrated (collected) in the image sensing area array of pixels. After completion of integration collected electrons are transported into a suitable storage area by the CCD transfer process and further from the storage area into the detection node where electron signal charge is converted into a voltage. The resulting voltage is then supplied to the output terminals of the sensor. In CMOS image sensors; charge is converted into a voltage directly in the pixels themselves without any transport and the resulting voltage, after appropriate buffering, is delivered to the output terminals through various scanning and addressing means. The description of a CCD image sensor can be found for example in U.S. Pat. No. 6,111,279 to Nakashiba. The description of a CMOS sensor can be found for example in U.S. Pat. No. 6,549,235 to Fossum. As the image sensing technology evolves there are constant demands for performance improvements, more pixels, and a constant demands for reduction of cost. The cost can be directly related to chip size and consequently to the pixel size. It is thus desirable to design high-resolution image sensors that have many pixels with very small size. There are, however, some obstacles and limitations in this process that need to be overcome first. The small pixel size results in smaller sensor sensitivity, since fewer photons impinge on the particular pixel. This could, theoretically, be overcome by longer integration times or more illumination intensity using a faster lens. However, smaller pixels also have a small well capacity and cannot collect (integrate) a sufficient amount of charge. Collection of only a small amount of charge results in large photon noise, which is a consequence of Poisson statistic that describes the random nature of photon arrivals to pixels. The conventional approach to image sensing, with full charge integration in pixels, followed by a subsequent readout, thus cannot be used and a new concept needs to be developed.